bendix



March 8, 1932.

V. BEN DIX BRAKE TESTING APPARATUS Filed sept. 27, 192B 3 Sheets-Sheet l A TTORNEY March s, 1932. v. BENDIX 1,848,457

BRAKE TESTI NG APPARATUS Filed Sept. 27, 1928 3 Sheets-Sheet 2 Figo 2 ATTORNEY March 8, 1932. v. BENDIX BRAKE TESTING .APPARATUS Filed Sept. 27, 1928 5 Sheets-Sheet 5 ATTORNEY treaddriving devices; L

Patented Mai. s, 1932 Tas APai'alai" OFI-ica mm1* BENDIX, OF CHICAGO, ILLINOIS, ASSIGNOB TO NATIONEAL BRAKE SERVICE,

C., O F CHICAGO, ILLINOIS, A 'CORPORATION'.OF ILLINOIS l BRAKE-TESTING APPARATUS appnmion mea september 27, 192s. serial No. 363,745.

This'invention relates to the testing of brakes, and is illustrated asembodied in a novel apparatus for testing four-wheel automobile brakes. Among the more important features o'f the invention may be enumerated (1) the use of bandplike devices, preferably of the caterpillar tread variety, for driving atleast two wheels against their brakes,pso

. that no adjustment need be made .for auto-v 110 mobiles of different wheel-bases; (2) ran arrangement ofgparts giving an unobstructed space'beneath the car to facilitate work on the brake operating mechanism beneath the car; and (3) a novel device for holding the 1 5 automobile .during the testing of the brakes.

rFhese and other features, including various novel arrangements and desirable particular constructions, will be apparent fromthe following descn'vption of one illustrative embodiment sho inthe vaccompanying drawindn which: v

' t igure 1 is a topplan view ofthe appara- Figure 2 is a `side elevation of the appara- -tus; Figure 3 is an-end elevation of the`ap paratushlooking downwardlyfrom the upper erd of Figure 1, but with the ramps omitted;

Figure 4 'is a detail sectional viewthr'ough ao'portion of one ofthe bandlike caterpillar Figure 5 is a'sec'tion through j mechanism adjacent one of the 'and-' E Figure 6 is a sectional view'through the driving mechanism taken at right angles. to theA lane of Figure 5.

e apparatus, in the illustrated embodiment, includes a pair of suitable inclined 'ramps 10l up which vthe automobile may be driven, and from whichthe wheels Vof Ythe automobile roll onto apair of band-like wheel-- driving devices 12, of a novel caterpillar type. The iront wheelsare carried from theseban'dlike devices 12, over stationary` ways ,114 car'-y ried by suitable framework 16, onto wheel-f driving rollers 18.

When the frontthe driving in Figure 2.-

diierentials;

` f ures- 5 and 6 is prel erably of theplanetary type and comprises a Worm gear 64- rotatably ingjf70. The smaller'spur gear portion of the wheels reach theirlfinal position on rollers 18, the automobile iszautomatically engaged and held by novelmeans such as a catch including a lever 20 pivoted 'on a supporting standard 22 carried by a bar extending across the front of the apparatus. The front endor nose of lever 2 0 is beveled to form a` wedge which is forced down by the axle in itsforward movement, against the resistance of a spring 26 tensioned between the support 22 and the^lever. The lever is Fut away to form a fixed abutment or hook 28 engaging one side of the axle, and is provided With a collar` 30pressed by a spring 32 toward a cross-pin34 forming a iixed stop. Collar; 30 forms an elastic stop to engage the front edge of the front axle of the car to be tested and through the resiliency of spring 32 return Athe axle to a position abut- 'ting the straight edge of hook 28, in which position the front wheels of the car will be 1n tread engagement with rollers 18. The

' axle is released, after testing thel brakes, by

pulling up on the left-hand end of lever 20 Each of rollers 18 is driven by a shaft 36 from a differential 38, the casing of which has aworm gear driven `by .a worm 40 from a source of power such as an electric motor 42. The other shaft 44 of the diierential, arrangedyin'the usual manner in end *to end alinement with respect to shaft 36, has an arm 46 connected by a link 48 to a measuring and indicating device 50 of the spring-scale type. Y

I hediiferential ear illustrated in Figmounted onshaft 36 and having an integral vsun gear 66 meshing with lthe step gear 68 rotatably mou'nted in and carried by the casstepg`ear 68 is meshe'd with spur gear 72, that is, keyed/@shaft 36. Casing '(0 is secured tofthe sh'aft 44 within the end 'of which is a bearing for the projecting end portion of shaft 36, :Rotation of the-worm 40 applies a turningdnomeiit to both shaft 36 and casing 70 but .'in/ thekenbodiment shown, shaft 44 is yieldin ly held against rotation by the,indi

eating/'device v 50 and motion for-'driving the Vrolls is transmitted entirely throughshaft 36.`

The novel caterpillar driving devices 12 are shown as including a series of tread plates 52 (Fig. 4) connected by pivots 54 having rollers 56 seated on tracks or ways formed on the frame 16. These devices run over drums or pulleys .58 and 60, the latter,

being driven as described for rollers 18. Thus the rear wheels may rest anywhere on the belt-like devices 12,.and it is not necessary to adjust the a paratus for testingv automobileshaving ldi erent wheelbases.

It is important to note that there is an entirely unobstructedspace 62 between the sides of the apparatus, and extending the full length of the apparatus except for the cross bar 24, support 22, and lever 20 at thel front end of the apparatus. This greatly facili tates work beneath the car.

While one illustrative embodiment has been described in detail, it is'not my intention to limit the scope of the invention to that v particular embodiment, or otherwise than by the terms of the appended claims.

I claim:

1. Apparatus for testing the brakes of an automobile comprising, in combination, four devices including driving shafts' and concentric housings therefor for rotating the four wheels of the automobile independently of each other against the resistance of their respective brakes, and means connected with the housings for measuring independently the forces necessary to drive said devices Aand to show the resistances of the several brakes, at least two of said devices including relatively long belt-like members engaging wheels on opposite sides of the automobile so that the four wheels are operatively engaged without adjusting .the apparatus for the varying wheelbases of .diiferent automo biles.

v gaged without adjusting the apparatus for the varying wheelbases of dierent automobiles and the other devices comprising wheelsupporting rollers. l

3.' Brake-testing apparatus comprising, in combinatioma pair of shafts arranged generally end to end and connected by a differential, power means for driving the diii'erential, wheel-rotating means, driven by one of said shafts, and measuring and indicating nmeans directly connected to the other of said shafts and yieldingly resisting rotation oi said other shaft.

4. Braketesting apparatus comprising, in t i and yieldingly resistingl rotation of said other shaft.

5. Brake-testing apparatus comprising, in

combination, means upon which an automov bile maybe driven and which supports the automobile wheel, and a shock absorbing latch device automatically operated by driving the automobile into place and which engages and holds the front axle of the automobile.

6. Brake-testing apparatus comprising, in

combination, means upon which an automo-` bile may be driven and which supports the automobile Wheel, and latch device automat'- icallyoperated by driving the automobile into place having a resilient" thrust absorbing member and which engages and holds a'part of the automobile.

7. An automobile-holding device comprising, in combination, a pivoted lever having an axle-gripping means at one end, said means .including relatively slidable jaws, and a springyieldingly urging the lever toward axle-gripping position, the lever being beveled e-to be wedged against the resistance of the spring by movement of an axle thereagainst and then to be moved back by said spring to grip the axle. y

8. Anautomobile-holding device comprlsing, in combination, a pivoted lever having a fixed shoulder and a`yieldingly-operated collar forming axle-gripping means,'and a spring yieldinglyurging the lever toward axle-grlpping position, the lever being beveled to be wedged against the resistance of the spring by movement of an axle thereagainst and then to be moved back by said spring to lgrip the axle.

9. In a brake testing device, the combination of a frame adapted tosupport a vehicle and a vehicle securing latch having a resilient abutment mounted thereon.

10. In a brake testing device, the combination of a frame adapted to support a vehicle,l and a vehicle securing latch having a pair of relatively movable jaws, one of which is resiliently urged toward the other.

In testimony whereof, I have hereunto signedamy name.

VINCENT BENDIX. 

